Brain Teasers
Confusing Math
A9543B represents a six-digit number in which A and B are digits different from each other. The number is divisible by 11 and also by 8.
What digit does A represent?
What digit does A represent?
Hint
The six-digit number is divisible by 8 and 11. Find B first.Answer
This might be a little confusing:Since the number is divisible by 8, the number 43B formed by the last three digits of the given number is divisible by 8. Digit B must be 2.
Since A95432 is divisible by 11, the difference between the sum of its odd-place digits and the sum of its even-place digits is 0 or a multiple of 11. In this case, the difference is 0. Then (A+5+3)-(9+4+2)=0 is equivalent to A+8=15 or A=7.
B=2
A=7
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Comments
ok , my head hurts now
Very interesting, but hard for a quick glance enjoyment In fact it made me feel pretty dumb! Means I need to spend more time with it, so into my favorites. Thanks
Easy for a maths freak like yours truly. Keep them coming.
gj, it was easy. cause i knew the division rules. very good job
I have a headache now.
ooowwww, oookkk, I think.....brain hurts good one though
That was very easy.
Although I had to admit it was a little too professional.
Although I had to admit it was a little too professional.
That was very easy.
Although I had to admit it was a little too professional.
Although I had to admit it was a little too professional.
I figured it easily enough, but had forgotten the 'divisible by 8' rule. Would have been simpler than my trial and error method. Very nice!
Very easy if you know your divisibility tesst but a reasonably good teaser fashioned from these rules.
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